Radiator Fan Circuit Troubleshooting (Without A/C)
Radiator Fan Circuit Troubleshooting
Without A/C
1. Check the No. 30 (30 A) fuse, and No. 10 (7.5 A) fuse in the under-dash fuse/relay box.
Are the fuses OK?
YES -
Reinstall the fuse, then go to step 2.
NO -
Replace the fuse(s) and recheck. If the fuse(s) blow again, repair the short to ground the No. 30 (30 A) fuse, and the No. 10 (7.5 A) fuse circuit.
2. Remove the radiator fan relay, and test it Testing and Inspection.
Is the relay OK?
YES -
Go to step 3.
NO -
Replace the radiator fan relay and recheck.
3. Measure the voltage between radiator fan relay 4P socket terminal No. 2 and body ground.
Is there battery voltage?
YES -
Go to step 4.
NO -
Repair an open in the wire between under-dash fuse/relay box connector B (36P) terminal No. 1 and radiator fan relay 4P socket terminal No. 2.
4. Disconnect the radiator fan motor 2P connector.
5. Check for continuity between radiator fan relay 4P socket terminal No. 1 and radiator fan motor 2P connector terminal No. 2.
Is there continuity?
YES -
Go to step 6.
NO -
Repair an open in the wire between radiator fan relay 4P socket terminal No. 1 and radiator fan motor 2P connector terminal No. 2.
6. Check for continuity between radiator fan motor 2P connector terminal No. 1 and body ground.
Is there continuity?
YES -
Go to step 7.
NO -
Repair an open in the wire between radiator fan motor 2P connector terminal No. 1 and body ground. If the wire is OK, check for a poor ground at G301 Left Engine Compartment Wire Harness (Dash Branch).
7. Test the fan motor Testing and Inspection.
Is the fan motor OK?
YES -
Go to step 8.
NO -
Replace the fan motor Radiator And A/C Condenser Fan, Motor, And Shroud Removal And Installation.
8. Turn the ignition switch to ON (II).
9. Measure the voltage between radiator fan relay 4P socket terminal No. 4 and body ground.
Is there battery voltage?
YES -
Go to step 10.
NO -
Repair an open in the wire between under-dash fuse/relay box connector B (36P) terminal No. 12 and radiator fan relay 4P socket terminal No. 4.
10. Turn the ignition switch to LOCK (0).
11. Connect the HDS to the DLC.
12. Turn the ignition switch to ON (II).
13. Make sure the HDS communicates with the vehicle and the ECM/PCM. If it does not communicate, troubleshoot the DLC circuit Testing and Inspection.
14. Jump the SCS line with the HDS, then turn the ignition switch to LOCK (0).
NOTE: This step must be done to protect the ECM/PCM from damage.
15. Disconnect ECM/PCM connector A (49P).
16. Check for continuity between radiator fan relay 4P socket terminal No. 3 and ECM/PCM connector terminal A6.
Is there continuity?
YES -
Update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM, then recheck. If the symptom/indicator goes away with a known-good ECM/PCM, replace the original ECM/PCM Service and Repair.
NO -
Repair an open in the wire between radiator fan relay 4P socket terminal No. 3 and ECM/PCM connector terminal A6.